Transfers the DNA message into a messenger wh/ then goes out into the cytoplasm and in the ribosome under the construction of RRNA builds the proteins

Three Different Types of RNA

1. TRNA

2. MRNA

3. RRNA

Transfer RNA (TRNA)

type of RNA wh/ helps undergo the process of transcription. transcribes the message from the DNA to the RNA

MRNA

type of RNA

takes the message from the TRNA brings it out into the cytoplasm into the ribosome

RRNA

type of RNA

final componenet of the RNA that takes the message from the MRNA to put together the amino acids in the polypeptides and the peptide bonds that sequence amino acids and builds the protein

tissue

a group of cells that usually have a common origin in an embryo and function together to carry out specialized activities.

4 Types of Tissue

1. Epithelial

2. Connective

3. Nervous

4. Muscle

connective tissue composition

two basic elements

1. extracellular matrix

2. cells

extracellular matrix

material located between its widely spaced cells. consists of:

1. protein fibers

2. ground substance

extracellular fibers found in the extracellular matrix...

secreted by the connective tissue cells and account for many of the functional properties of the tissue in addition to controlling the surrounding watery enviroment via specific proteoglycan molecules.

ground substance

may be fluid, semifluid, gelatinous, or calcified.

supports cells, binds them together, stores water, and provides a medium for exchange of substances between the blood and cells.

plays an active role in how tissues develop, migrate, proliferate, and change shape, and in how they carry out their metabolic functions.

types of connective tissue cells

1. fibroblasts

2. macrophages

3. plasma

4. mast

-blasts

"to bud or sprout"

each major type of CT contains an immature class of cells ending in -blasts.

fibroblasts

1. large

2. flat

3. w/ branching processes

present in all CT, secrettin the fibers & certain components of the ground substance of the extracullular matrix.

small cells that develop from a type of white blood cell called a B lymphocyte. plasma cells secrete antibodies, proteins that attack or neutralize foreign substances in the body. (most are found in CT, especially in the gastrointestinal & respiratory tracts. also abundant in salivary glands, lymph nodes, spleen & red bone marrow.)

leukocytes (white blood cells)

not found in significant numbers in normal CT. however, in response to certain conditions they migrate from blood into connective tissue. for example, neutroplils gather at sites of infection, and eosinophils migrate to sites of parasitic and ALERGIC RESPONSES.

MAST

produce histamine, a chemical that dilates small blood vessels as part of the inflammatory response, the body's reaction to injury or infection.

secretions are synthesized on ribosomes attached to rough ER; processed, sorted, and packaged by the Golgi complex; and released from the cell in secretory vesicles via exocytosis. ie salavary glands, pancreas

apocrine

accumulate their secretory product at the apical surface of the secreting cell. then that portion of the cell pinches off by exocytosis from the rest of the cell to release the secretion. the cell repairs itself to repeat the process. sweat glands.

simple cell layer

1 layer of cells

stratified cell layer

2 or more layer of cells

pseudostratified cell layer

columnar epithelium

(shaped like funky stained glass)

squamous

are thin, which allows for the rapid passage of substances through them.

cubodial

as tall as they are wideand are shaped like cubes or hexagons. they may have microvilli at their apical surface and function in either secretion or absorption.

columnar

much taller than they are wide, like columns, and protect underlying tissues. Their apical surfaces may have cilia or microvilli, ad they often are specialized for secretion and absorption.

transitional

chage shape, from squamous to cuboidal and back, as organs such as the urinary bladder stretch (distend) to a larger size and then collapse to a smaller size.

connective tissue (CT)

protects & supports the body & it's organs.

1. binds organs together

2. stores energy

3. provides immunity

muscular tissue

specialized cells for contracting & generation of force & in the process generates heat to warm the body.